Merge branch 'bpf-libbpf-deprecated-cleanup'

Andrii Nakryiko says:

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Clean up remaining missed uses of deprecated libbpf APIs across samples/bpf,
selftests/bpf, libbpf, and bpftool.

Also fix uninit variable warning in bpftool.
====================

Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>